Transport device including an actuating tape NIP

ABSTRACT

A transport device for transporting printed products is provided including a first and a second tape for receiving and transporting the printed products, a first and second roller for guiding the tapes, a nip-adjusting device adjusting a nip formed by the first and second tapes at the first and second rollers and a sensor determining a thickness of the printed products, the nip adjusting device being actuated as a function of the sensor. A method is also provided.

BACKGROUND

The present invention relates generally to printing presses and moreparticularly to a transport device for transporting printed products.

U.S. Pat. No. 4,196,835, hereby incorporated by reference herein,discloses an improved collating machine which includes a stitcherassembly which stitches a group of signatures while they are moving. Asaddle conveyor travels past a collating station and individualsignatures are fed from the collating station onto the conveyor to formthe group of collated signatures. The conveyor carries the group ofcollated signatures through the stitcher assembly which binds thesignatures in each group together.

U.S. Pat. No. 4,482,141, hereby incorporated by reference herein,discloses a method and device for conveying signatures from a bladechain conveyor supporting the signatures directly at a fold line. Thesignatures are gripped from above by orbitally-rotating clamping pads,which then transfer the signatures to a belt conveyor perpendicular tothe blade chain conveyor.

U.S. Pat. No. 6,616,139 discloses a device for removing printedproducts, having a fold and being transported uniformly spaced andastraddle by a transport device, that has a rotatingly driven grippingdevice with controlled gripping elements for gripping one of the printedproducts by the fold on the transport device and removing the printedproduct while stably holding the printed product.

U.S. Pat. No. 6,918,729 discloses a method and device for trimming abook. A conveying device including an orbital turn unit grips thepartially trimmed book, rotates the book 90 degrees and transfers thebook to a registration device.

BRIEF SUMMARY OF THE INVENTION

The present invention provides a transport device for transportingprinted products including:

a first and a second tape for receiving and transporting the printedproducts,

a first and second roller for guiding the tapes,

a nip-adjusting device adjusting a nip formed by the first and secondtapes at the first and second rollers, and

a sensor determining a thickness of the printed products, the nipadjusting device being actuated as a function of the sensor.

The present invention also provides a method for transporting printedproducts including the steps of:

setting a nip to a first size for printed products having a firstthickness,

sensing a printed product having a second thickness different from thefirst thickness, the printed product sensing occurring prior to theprinted product entering the nip,

adjusting the first size of the nip, to a second size different from thefirst size, to receive the printed product having a second thickness,and

transporting the printed product having the second thickness through thenip.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the present invention will be elucidated withreference to the drawings, in which:

FIG. 1 shows a transport device according to the present invention;

FIG. 2 shows a cross section of the transport device;

FIG. 3 shows another cross section of the transport device; and

FIG. 4 shows a view of nip-adjusting device of the transport device.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT

FIG. 1 shows a preferred embodiment of a transport device 10 includingtransport tapes 12, 14, 112, 114, wheel 18 and nip-adjusting devices 30,130. The transport device 10 adjusts to transport printed products, suchas books, of varying thicknesses. A nip 70 (FIG. 2) is initially set totransport books 60 with a predetermined thickness. Grippers 110, whichmay be grippers similar to those disclosed in U.S. Pat. No. 4,482,141,grip and carry books 60, 62 to transport device 10 via nip 70. When adifferent thickness book 62 is detected by a sensor 80, a controller 100adjusts the size of nip 70 to accommodate incoming book 62, as shown inFIG. 3. Once book 62 is transported, the nip 70 may return back to theinitial size before receiving the next book.

As shown in FIG. 2, a nip 70 is formed between rollers 20, 21 andtransport tapes 12, 14. Transport tape 12 travels around tape rollers20, 20′, 20″, 20′″ and idle roller 15. Transport tape 14 travels aroundroller 21, wheel 18 and idle roller 16. Nip-adjusting device 30 is setinitially so transport tapes 12, 14 receive books 60 with apredetermined thickness and transport books 60 around wheel 18.

Nip-adjusting device 30 connects to tape rollers 20, 21 via roller arms22, 23, shafts 34, 35 and housings 24, 25. Tape rollers 20, 21 aremounted to roller arms 22, 23 which are fixed to shafts 34, 35. Shaftsare supported by housings 24, 25 shown in FIG. 1. Attached to anopposite end of shafts 34, 35 are levers 32, 33 shown in FIG. 4.

As shown in FIGS. 2 and 3, nip 70, in an initial size in FIG. 2, isadjusted to accommodate a thinner book 62. In FIG. 3, the horizontaldistance between tape rollers 20 and 21 is decreased so the size of nip70 is smaller. Nip-adjusting device 30 controls the movement of taperollers 20 and 21 to vary the size of nip 70. Thus, for example, when anincomplete book 62 occurs, the transport tapes 12, 14 can properlytransport the incomplete book. Without the automatic adjustment, jammingor dropping of incomplete book 62 may occur.

As shown in FIG. 4, nip-adjusting device 30 includes levers 32, 33 withcam followers 42, 43. Levers 32, 33 are spring loaded toward a cam 40via a spring connector 39. Cam 40 includes a cam surface 41 having ageometry providing high dwells 46, 47 and low dwells 48, 49. Anadjustable handle 38 secures a lever 36 to cam 40. Lever 36 and cam 40both rotate around axis 44. Handle 38 may be adjusted in slot 37 tochange the rotation of cam 40, setting the initial size of nip 70 asdesired.

Nip-adjusting device 30 also includes prong 54, shaft 52 and pneumaticcylinder 50. Prong 54 is fixed to lever 36 by pin 56. When controller100 actuates nip-adjusting device 30, pneumatic cylinder 50 causes shaft52 to retract or extend, rotating lever 36. This movement of lever 36rotates cam 40 about axis 44 in the counterclockwise or clockwisedirection, respectively.

As shown in FIGS. 1 to 4, nip 70 is set initially to receive a book 60,already being conveyed by transport tapes 12, 14, 112, 114 in adirection B. A sensor 80 detects a thin book 62 and relays message tocontroller 100. Controller 100 activates nip-adjusting devices 30, 130.Pneumatic cylinder 50 retracts shaft 52. As shaft 52 is retracted lever36 rotates in the counterclockwise direction via pin 56 and prong 54.Cam followers 42, 43 approach low dwells 48, 49 of cam 40. Subsequently,levers 32, 33 pivot towards one another which cause roller arms 22, 23to move towards one another via shafts 34, 35. The movement of rollerarms 22, 23 towards each other shortens the horizontal distance betweentape rollers 20 and 21 thereby reducing the size of nip 70. Thus, nip 70closes in on book 62 so transport tapes 12, 14, 112, 114 contact andtransport thin book 62 in a direction A.

The transport device may include two separate nip-adjusting devices totransfer unbalanced books that are thicker on one end. Nip-adjustingdevice 30 can be actuated independently of nip-adjusting device 130 toadjust for unbalanced thickness at one end with respect to the otherend.

Preferably, the timing of the actuating devices is such that the nipcloses on the book and not before the book. This reduces or eliminatesthe impact from transferring an incomplete thick book into a closed nip.

In the preceding specification, the invention has been described withreference to specific exemplary embodiments and examples thereof. Itwill, however, be evident that various modifications and changes may bemade thereto without departing from the broader spirit and scope of theinvention as set forth in the claims that follow. The specification anddrawings are accordingly to be regarding in an illustrative mannerrather a restrictive sense.

1. A transport device for transporting printed products comprising: afirst and a second tape for receiving and transporting the printedproducts; a first and second roller for guiding the tapes; anip-adjusting device adjusting a nip formed by the first and secondtapes at the first and second rollers; and a sensor determining athickness of the printed products, the nip adjusting device beingactuated as a function of the sensor.
 2. The transport device as recitedin claim 1 wherein the first and second rollers are connected to a firstand second cam follower via a first and second shaft.
 3. The transportdevice as recited in claim 1 where in the nip-adjusting device includesa cam.
 4. The transport device as recited in claim 1 wherein thenip-adjusting device includes a pneumatic cylinder.
 5. The transportdevice as recited in claim 1 further comprising a controller.
 6. Thetransport device as recited in claim 1 further comprising a furthernip-adjusting device independently actuatable with respect to thenip-adjusting device.
 7. A method for transporting printed productscomprising the steps of: setting a nip to a first size for printedproducts having a first thickness; sensing a printed product having asecond thickness different from the first thickness, the printed productsensing occurring prior to the printed product entering the nip;adjusting the first size of the nip, to a second size different from thefirst size, to receive the printed product having a second thickness;and transporting the printed product having the second thickness throughthe nip.
 8. The method as recited in claim 7 wherein the printed productis gripped prior to the printed product entering the nip.
 9. The methodas recited in claim 7 further comprising the step of returning the sizeof the nip from the second size to the first size automatically.